Conventionally, as the position holding device of this type, there has been known one disclosed in Patent Literature 1. This position holding device for a rotating lever includes a rotating lever rotatably supported by a base member in such a manner that the rotating lever abuts against a first stopper member to be held at a first position, and abuts against a second stopper member to be held at a second position, and a torsion spring that is interposed between the rotating lever and the base member, urges the rotating lever toward the first stopper member at the first position, and urges the rotating lever toward the second stopper member at the second position. The rotating lever can be held elastically at the two positions including the first position and the second position.
The torsion spring employed in this conventional device includes a coiled part mounted to be rotatable about a boss portion provided upright to the base member, and a first arm part and a second arm part that extend from the coiled part in a radial direction substantially orthogonal to an axial direction of the boss portion and face each other across an engagement portion provided to the rotating lever.